/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */

package org.apache.iotdb.db.engine.querycontext;

import org.apache.iotdb.db.exception.query.QueryProcessException;
import org.apache.iotdb.db.query.reader.chunk.MemAlignedChunkLoader;
import org.apache.iotdb.db.utils.datastructure.AlignedTVList;
import org.apache.iotdb.db.utils.datastructure.TVList;
import org.apache.iotdb.tsfile.common.conf.TSFileDescriptor;
import org.apache.iotdb.tsfile.file.metadata.AlignedChunkMetadata;
import org.apache.iotdb.tsfile.file.metadata.ChunkMetadata;
import org.apache.iotdb.tsfile.file.metadata.IChunkMetadata;
import org.apache.iotdb.tsfile.file.metadata.enums.TSDataType;
import org.apache.iotdb.tsfile.file.metadata.enums.TSEncoding;
import org.apache.iotdb.tsfile.file.metadata.statistics.Statistics;
import org.apache.iotdb.tsfile.read.common.TimeRange;
import org.apache.iotdb.tsfile.read.reader.IPointReader;
import org.apache.iotdb.tsfile.write.schema.IMeasurementSchema;

import java.io.IOException;
import java.util.ArrayList;
import java.util.List;

public class AlignedReadOnlyMemChunk extends ReadOnlyMemChunk {

    private final String timeChunkName;

    private final List<String> valueChunkNames;

    private final List<TSDataType> dataTypes;

    /**
     * The constructor for Aligned type.
     *
     * @param schema       VectorMeasurementSchema
     * @param tvList       VectorTvList
     * @param deletionList The timeRange of deletionList
     */
    public AlignedReadOnlyMemChunk(
            IMeasurementSchema schema, TVList tvList, List<List<TimeRange>> deletionList)
            throws QueryProcessException {
        super();
        this.timeChunkName = schema.getMeasurementId();
        this.valueChunkNames = schema.getSubMeasurementsList();
        this.dataTypes = schema.getSubMeasurementsTSDataTypeList();
        int floatPrecision = TSFileDescriptor.getInstance().getConfig().getFloatPrecision();
        List<TSEncoding> encodingList = schema.getSubMeasurementsTSEncodingList();
        this.tsBlock =
                ((AlignedTVList) tvList).buildTsBlock(floatPrecision, encodingList, deletionList);
        initAlignedChunkMetaFromTsBlock();
    }

    private void initAlignedChunkMetaFromTsBlock() throws QueryProcessException {
        // time chunk
        Statistics timeStatistics = Statistics.getStatsByType(TSDataType.VECTOR);
        IChunkMetadata timeChunkMetadata =
                new ChunkMetadata(timeChunkName, TSDataType.VECTOR, 0, timeStatistics);
        List<IChunkMetadata> valueChunkMetadataList = new ArrayList<>();
        // update time chunk
        for (int row = 0; row < tsBlock.getPositionCount(); row++) {
            timeStatistics.update(tsBlock.getTimeColumn().getLong(row));
        }
        timeStatistics.setEmpty(false);
        // update value chunk
        for (int column = 0; column < tsBlock.getValueColumnCount(); column++) {
            Statistics valueStatistics = Statistics.getStatsByType(dataTypes.get(column));
            valueStatistics.setEmpty(true);
            switch (dataTypes.get(column)) {
                case BOOLEAN:
                    for (int row = 0; row < tsBlock.getPositionCount(); row++) {
                        if (!tsBlock.getColumn(column).isNull(row)) {
                            long time = tsBlock.getTimeColumn().getLong(row);
                            valueStatistics.update(time, tsBlock.getColumn(column).getBoolean(row));
                        }
                    }
                    break;
                case TEXT:
                    for (int row = 0; row < tsBlock.getPositionCount(); row++) {
                        if (!tsBlock.getColumn(column).isNull(row)) {
                            long time = tsBlock.getTimeColumn().getLong(row);
                            valueStatistics.update(time, tsBlock.getColumn(column).getBinary(row));
                        }
                    }
                    break;
                case FLOAT:
                    for (int row = 0; row < tsBlock.getPositionCount(); row++) {
                        if (!tsBlock.getColumn(column).isNull(row)) {
                            long time = tsBlock.getTimeColumn().getLong(row);
                            valueStatistics.update(time, tsBlock.getColumn(column).getFloat(row));
                        }
                    }
                    break;
                case INT32:
                    for (int row = 0; row < tsBlock.getPositionCount(); row++) {
                        if (!tsBlock.getColumn(column).isNull(row)) {
                            long time = tsBlock.getTimeColumn().getLong(row);
                            valueStatistics.update(time, tsBlock.getColumn(column).getInt(row));
                        }
                    }
                    break;
                case INT64:
                    for (int row = 0; row < tsBlock.getPositionCount(); row++) {
                        if (!tsBlock.getColumn(column).isNull(row)) {
                            long time = tsBlock.getTimeColumn().getLong(row);
                            valueStatistics.update(time, tsBlock.getColumn(column).getLong(row));
                        }
                    }
                    break;
                case DOUBLE:
                    for (int row = 0; row < tsBlock.getPositionCount(); row++) {
                        if (!tsBlock.getColumn(column).isNull(row)) {
                            long time = tsBlock.getTimeColumn().getLong(row);
                            valueStatistics.update(time, tsBlock.getColumn(column).getDouble(row));
                        }
                    }
                    break;
                default:
                    throw new QueryProcessException("Unsupported data type:" + dataTypes.get(column));
            }
            if (valueStatistics.getCount() > 0) {
                IChunkMetadata valueChunkMetadata =
                        new ChunkMetadata(
                                valueChunkNames.get(column), dataTypes.get(column), 0, valueStatistics);
                valueChunkMetadataList.add(valueChunkMetadata);
                valueStatistics.setEmpty(false);
            } else {
                valueChunkMetadataList.add(null);
            }
        }
        IChunkMetadata alignedChunkMetadata =
                new AlignedChunkMetadata(timeChunkMetadata, valueChunkMetadataList);
        alignedChunkMetadata.setChunkLoader(new MemAlignedChunkLoader(this));
        alignedChunkMetadata.setVersion(Long.MAX_VALUE);
        cachedMetaData = alignedChunkMetadata;
    }

    @Override
    public boolean isEmpty() throws IOException {
        return tsBlock.isEmpty();
    }

    @Override
    public IPointReader getPointReader() {
        return tsBlock.getTsBlockAlignedRowIterator();
    }
}
